The first step I would recommend is to get on the same page And set the goal. from there the path probably isn't incredibly different depending on equity on the house you bought you might try and refinance and pull money out for a down payment on the next property whatever property that is.alternate methods of buying another property would be things like seller financing hard money private money or if you have the means obviously cash.But seriously the best thing I can tell you is to make sure you guys are on the same page and pushing towards the same goal If you're not it's going to be miserable

I will be doing private financing through the owner to get the land.

I have already consulted city planning officials, architect, surveyor and bank and private lenders. 

You might be better off telling all your family and friends what you doing and trying to raise some private money.  

If you don't mind, I'd be interested to know which banks you tried working with via private message?

One of the main things that seem to allude to me is what sort of paperwork do Private lenders want to see when someone is asking for a loan? 

Have you thought about investing in someone else's deal as a private lender to get your principal plus interest returned to you?

Specifically I would like to get into small multifamily properties and possibly brrrr-ing them I already have secured a private lender who has capital.

As mentioned, the other option is private money, a JV partner, or hard money which will be expensive.

I am working on a project to develop an effective digital application for private landlords (focusing on 10 doors or less).